Abstract: Objective To measure the electrophysiological response of the Haller's organ of starving adult female Haemaphysalis longicornis ticks to several odor volatiles,and to provide a basis for further research on the host selection mechanism of ticks.Methods Electroantennogram with glass electrodes was used to measure the electroantennography (EAG) values of the Haller's organ of adult female H.longicornis ticks to glacial acetic acid,ammonia,and the blood,fecal,and fur extracts of Kunming mice,New Zealand rabbits,and sheep after 1 or 4 months of starvation,and the differences in data were analyzed for t test and analysis of variance using SPSS 22.0 software.Results Except for a relatively low EAG response value (0.000 mV) to glacial acetic acid with a concentration of 0.10 μl/ml,the Haller's organ of starving adult female H.longicornis showed varying degrees of electrophysiological reactions to glacial acetic acid and ammonia at concentrations of 1.00,10.00,and 100.00 μl/ml,and the degree of electrophysiological reactions increased with the increasing concentrations;The EAG values at different concentrations of glacial acetic acid and ammonia of Haller's organ of ticks in 1 month of starvation were higher than those of ticks in 4 months of starvation,but only EAG values at 1.00,10.00,and 100.00 μl/ml of glacial acetic acid,and 1.00 and 100.00 μl/ml of ammonia were significantly different between ticks with different times of starvation (all P<0.05).The ticks with starvation for 1 and 4 months showed the highest EAG response value to 100 μl/ml ammonia,i.e.,(2.729±0.129) mV and (2.239±0.285) mV,respectively,and the EAG response values to each concentration of ammonia were significantly higher than those to each concentration of glacial acetic acid (all P<0.05).The H.longicornis ticks after starvation for 1 month had similar EAG response values to the blood of Kunming mice,New Zealand rabbits,and sheep (F=0.002,P=0.998),and as for the three kinds of animals,the ticks had relatively high EAG response values to the fecal and fur extracts of sheep,i.e.,(0.758±0.070) mV and (0.914±0.150) mV,respectively,which were significantly higher than the EAG response values to the fecal and fur extracts of the other two kinds of animals (fecal extract:F=11.587,P=0.001;fur extract:F=14.237,P<0.001).Conclusion At the same concentration,The Haller's organs of the adult female ticks of H.longicornis are more sensitive to ammonia than to glacial acetic acid,and the ticks after starvation for 1 month have stronger EAG response to ammonia and glacial acetic acid than those after starvation for 4 months.The EAG response of ticks to the fecal and fur extracts of sheep are stronger than those to the fecal and fur extracts of Kunming mice and New Zealand rabbits.

Key words: Haemaphysalis longicornis, Odor, Electroantennography

摘要： 目的 测定饥饿长角血蜱雌成蜱哈氏器对几种气味物质的电生理反应，为进一步研究蜱对宿主的选择机制提供基础。方法 利用玻璃电极触角电位仪测定饥饿1和4个月长角血蜱雌成蜱哈氏器对冰醋酸、氨水以及昆明小鼠、新西兰兔、绵羊3种动物血液、粪便提取液和毛皮提取液的触角电位（EAG）反应值；数据间差异用SPSS 22.0软件进行t检验和方差分析。结果 饥饿长角血蜱雌成蜱哈氏器除对浓度为0.10 μl/ml的冰醋酸EAG反应值较低（0.000 mV）外，对1.00、10.00和100.00 μl/ml的冰醋酸和氨水均引起不同程度电生理反应，且均随着浓度的增大而增大。饥饿1个月的蜱哈氏器对不同浓度的冰醋酸和氨水的EAG值均大于饥饿4个月蜱的EAG值，但冰醋酸仅在1.00、10.00和100.00 μl/ml、氨水在1.00、100.00 μl/ml浓度，饥饿不同时间的蜱哈氏器对其EAG值差异有统计学意义（均P<0.05）。饥饿1和4个月的蜱哈氏器对100.00 μl/ml氨水的EAG反应值最大，分别为（2.729±0.129）和（2.239±0.285） mV，各浓度的氨水所产生的EAG值均高于各浓度的冰醋酸，且差异均有统计学意义（均P<0.05）。饥饿1个月的长角血蜱成蜱哈氏器对昆明小鼠、新西兰兔和绵羊血液的EAG反应值无统计学意义（F_血=0.002，P=0.998）；3种动物中，蜱对绵羊的粪便提取液和毛皮提取液EAG反应值均较大，分别为（0.758±0.070）和（0.914±0.150） mV，且与其他2种动物粪便提取液和毛皮提取液的EAG反应值差异均有统计学意义（（F_粪=11.587，P=0.001；F_皮=14.237，P<0.001）。结论 相同浓度条件下，长角血蜱雌成蜱哈氏器对氨水的反应比对冰醋酸的反应更加敏感，且饥饿1个月的蜱哈氏器对氨水和冰醋酸的EAG反应强于饥饿4个月的蜱；雌成蜱哈氏器对绵羊的粪便提取液和毛皮提取液的EAG反应均强于昆明小鼠、新西兰兔。

关键词: 长角血蜱, 气味, 触角电位